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41.
Sarcocystis sporocysts from the intestines of 2 opossums (Didelphis albiventris) from Argentina were fed to gamma-interferon knockout (KO) and nude mice. Protozoal schizonts were seen in brain, liver, spleen, and adrenal glands of mice examined 33-64 days after feeding sporocysts. Sarcocysts were seen in skeletal muscles of KO mice 34-71 days after feeding sporocysts. Schizonts and sarcocysts were structurally similar to Sarcocystis speeri Dubey and Lindsay, 1999 seen in mice fed sporocysts from the North American opossum Didelphis virginiana from the United States. 相似文献
42.
Post-transfusion malaria in thalassaemia patients 总被引:1,自引:0,他引:1
A total of 125 beta-thalassaemia patients receiving repeated blood transfusions were screened by Giemsa stain, Acridine-orange stain and antigen detection for evidence of malaria infection on each visit. A total of 8 (6.4%) of the patients developed post-transfusion malaria (PMT) as confirmed by tracing the infected blood donors. A high incidence of PTM in thalassaemia patients appears to be due to the use of fresh blood and the high frequency of blood transfusions required by these patients. Antigen detection using monoclonal antibody was found to be more sensitive for diagnosis of PTM and for screening suspected donors than the conventional blood smear examination methods and is therefore recommended for routine blood donor screening to rule out malaria infection. 相似文献
43.
J R Dubey G C Johnson A Bermudez K W Suedmeyert D L Fritz 《The Journal of parasitology》2001,87(6):1317-1322
A Sarcocystis neurona-like parasite was associated with acute sarcocystosis in the brain of an ibis (Carphibis spinicollis). Numerous schizonts and merozoites were found extravascularly in encephalitic lesions. These schizonts reacted positively with anti-S. neurona and anti-S. falcatula polyclonal antibodies in an immunohistochemical test. Sarcocysts of an unidentified Sarcocystis species were present in the brain, heart, and skeletal muscles. Sarcocysts in skeletal muscles were microscopic, and the sarcocyst wall was up to 3 microm thick. The villar protrusions on the sarcocyst wall were up to 4.5 microm long, constricted at the base, and expanded laterally. Schizonts and sarcocysts distinct from those of S. falcatula. 相似文献
44.
Of 1,564 serum samples from adult ewes from 33 farms in Iowa, Minnesota, South Dakota, Kansas, and Nebraska where toxoplasmosis-induced ovine abortions had been diagnosed, 65.5% were found positive for Toxoplasma gondii antibodies using the modified agglutination test. Toxoplasma gondii antibody titers of ewes were: less than 64 (34.5%), 64 (14.9%), 256 (22.0%), 1,024 (14.5%), and greater than 4,096 (13.8%). Thus, 28.3% of sheep had high titers (greater than 1,024) indicating recently acquired T. gondii infection. On certain farms, up to 95% of ewes were seropositive. Prevalence of T. gondii antibodies increased with age of the ewe. Of 665 ewes, 53.6% of 1-yr-old ewes were seropositive (titers greater than 64) versus 75% of 5-yr-old ewes. Results indicate that T. gondii infection in sheep in the United States is widespread. 相似文献
45.
Abhimanyu Jogawat Shreya Saha Madhunita Bakshi Vikram Dayaman Manoj Kumar Meenakshi Dua Ajit Varma Ralf Oelmüller Narendra Tuteja Atul Kumar Johri 《Plant signaling & behavior》2013,8(10)
Piriformospora indica association has been reported to increase biotic as well as abiotic stress tolerance of its host plants. We analyzed the beneficial effect of P. indica association on rice seedlings during high salt stress conditions (200 and 300 mM NaCl). The growth parameters of rice seedlings such as root and shoot lengths or fresh and dry weights were found to be enhanced in P. indica-inoculated rice seedlings as compared with non-inoculated control seedlings, irrespective of whether they are exposed to salt stress or not. However, salt-stressed seedlings performed much better in the presence of the fungus compared with non-inoculated control seedlings. The photosynthetic pigment content [chlorophyll (Chl) a, Chl b, and carotenoids] was significantly higher in P. indica-inoculated rice seedlings under high salt stress conditions as compared with salt-treated non-inoculated rice seedlings, in which these pigments were found to be decreased. Proline accumulation was also observed during P. indica colonization, which may help the inoculated plants to become salt tolerant. Taken together, P. indica rescues growth diminution of rice seedlings under salt stress. 相似文献
46.
Plant growth promotion and suppression of charcoal‐rot fungus (Macrophomina phaseolina) in velvet bean (Mucuna pruriens L.) by root nodule bacteria 下载免费PDF全文
Abhinav Aeron Dinesh Kumar Maheshwari Shrivardhan Dheeman Mohit Agarwal Ramesh Chand Dubey Vivek K. Bajpai 《Journal of Phytopathology》2017,165(7-8):463-478
Root‐nodulating bacteria are intimate associates of legumes. From a pool of rhizobia isolated from root nodules of Mucuna pruriens (Velvet bean/Kaunch), RMP66 and BMP17 were found to be capable of promoting siderophore and IAA production and phosphate solubilization (insoluble tri‐calcium). Both symbionts were studied further to determine their abilities to promote plant growth and to control root‐rot in Mucuna pruriens caused by the pathogenic plant fungus Macrophomina phaseolina. RMP66 and BMP17 were selected based on their excellent inhibitory activities against M. phaseolina (by 78% and 71%, respectively) in dual culture and in agar‐well assays using cell‐free culture filtrate (CFCF) (by 76% and 62%, respectively). Both strains inhibited fungal growth to a greater extent in iron‐deficient medium (51% and 69%) than in iron‐supplemented medium (37% and 0%), respectively. CFCFs of RMP66 and BMP17 obtained from Pikovskaya's broth and tryptophan‐amended YEM broth inhibited fungal growth by 80%‐55% and 70%‐43%, respectively, and were identified as Sinorhizobium meliloti RMP66 and Bradyrhizobium diazoefficiens BMP17 by 16S rDNA sequencing. Centrifuged and pelleted cells harvested from exponentially grown cultures of S. meliloti RMP66 and B. diazoefficiens BMP17 were used to bacterize seeds of M. pruriens, which then showed enhanced seed germination (by up to 17% and 12%, respectively), and subsequent increases in other plant growth parameters in field trials. Considerable increases in seedling vigour indices (62%: 53% and 110%: 130%) and biomass (8%: 13% and 25%: 28%) were also observed for bacterial treatments. Tn5‐mediated antibiotic‐resistant marker strains showed enhanced nodule occupancy by up to 72% and 68%, respectively. This study describes a multifunctional legume nodule rhizobia that could be utilized in multicropping systems under different agroclimatic conditions as a bioinoculant and alternative to fertilizers. 相似文献
47.
Nirogi RV Deshpande AD Kambhampati R Badange RK Kota L Daulatabad AV Shinde AK Ahmad I Kandikere V Jayarajan P Dubey PK 《Bioorganic & medicinal chemistry letters》2011,21(1):346-349
N1-Arylsulfonyl-3-piperazinyl indole derivatives were designed and identified as a novel class of 5-HT6 receptors ligands. All the compounds have high affinity and antagonist activity towards 5-HT6 receptor. The compound 7a (Ki = 3.4 nM, functional assay IC50 = 310 nM) shows enhanced cognitive effect when tested in NORT and Morris water maze models. Synthesis, SAR and PK profile of these novel compounds constitute the subject matter of this Letter. 相似文献
48.
49.
Illegal hunting has been a major threat for the survival of wildlife fauna, including the three crocodile species that India harbours: Crocodylus palustris, Crocodylus porosus and Gavialis gangeticus. Although law prevents trade on these species, illicit hunting for trade continues to threaten the survival of these endangered species; conservation strategies therefore require a rapid molecular identification technique for Indian crocodiles. A multiplex polymerase chain reaction (PCR) assay with species-specific primers, considered as one of the most effective molecular techniques, is described herein. The primers were designed to yield species-specific sized amplicons. The assay discriminates the three Indian crocodile species unambiguously within a short time period using only simple agarose gel electrophoresis. We recommend this multiplex PCR assay to be used in the identification of Indian crocodile species. 相似文献
50.
Najm FJ Zaremba A Caprariello AV Nayak S Freundt EC Scacheri PC Miller RH Tesar PJ 《Nature methods》2011,8(11):957-962
Myelin-related disorders such as multiple sclerosis and leukodystrophies, for which restoration of oligodendrocyte function would be an effective treatment, are poised to benefit greatly from stem cell biology. Progress in myelin repair has been constrained by difficulties in generating pure populations of oligodendrocyte progenitor cells (OPCs) in sufficient quantities. Pluripotent stem cells theoretically provide an unlimited source of OPCs, but current differentiation strategies are poorly reproducible and generate heterogenous populations of cells. Here we provide a platform for the directed differentiation of pluripotent mouse epiblast stem cells (EpiSCs) through defined developmental transitions into a pure population of highly expandable OPCs in 10 d. These OPCs robustly differentiate into myelinating oligodendrocytes in vitro and in vivo. Our results demonstrate that mouse pluripotent stem cells provide a pure population of myelinogenic oligodendrocytes and offer a tractable platform for defining the molecular regulation of oligodendrocyte development and drug screening. 相似文献